Typical mobile terminals and USIM ((Universal Subscriber Identity Module) or SIM (Subscriber Identity Module)) cards to be inserted into the mobile terminals store therein emergency call code information, which is information about the call numbers of emergency agencies, such as the police and fire departments. Such mobile terminals that store therein the emergency call code information include, for example, mobile terminals complying with “Release 99” of the 3GPP (3rd Generation Partnership Project) and successive specifications. The mobile terminal compares call number information, which indicates a call number to be called, with the stored emergency call code information. If they are not identical, the mobile terminal transmits a signal called SETUP to a Mobile-services Switching Centre (MSC) via a mobile communication base station (Node B/Base Transceiver Station (BTS)) and a Radio Network Controller (RNC) to generate a normal call. If they are identical, the mobile terminal transmits a signal called EMERGENCY SETUP to the MSC via the Node B/BTS and the RNC to generate an emergency call.
Most of the mobile terminals and the USIM cards store therein the emergency call code information of the country where the mobile terminals and the USIM cards are sold and the emergency call code information is different from country to country; therefore, the mobile terminal cannot transmit the signal called EMERGENCY SETUP to the mobile communication base station to generate the emergency call in countries other than the country where it is sold.
To solve the problem, a mobile terminal complying with the 3GPP specification “Release 5” receives emergency call code information and the Service Category from the MSC when an Attach is completed (i.e., when receiving an ATTACH ACCEPT) or when location registration is completed (i.e., when receiving a LOCATION UPDATING ACCEPT/ROUTING AREA UPDATE ACCEPT). With this configuration, even if the emergency call code indicated by the emergency call code information stored in the mobile terminal or the USIM card is different from the address of the emergency agency in the country where the mobile terminal is located now, the mobile terminal can generate an emergency call by transmitting the EMERGENCY SETUP signal using the received emergency call code information. The above-described Service Category is emergency-agency based attribute values that are defined in the 3GPP specification “Release 4” as the international standards. As a technology for allowing a mobile terminal to generate an emergency call, Japanese National Publication of International Patent Application No. 2003-526296 discloses a technology to set up, in response to the generation of an emergency call attached with a Service Category, a communication with an emergency agent corresponding to the Service Category on the mobile communication network.
Status transmission of the above-described mobile terminal during a process of selecting a mobile communication base station (Cell Selection/Reselection) is described below. FIG. 19 is a diagram that illustrates the status transmission in the Cell Selection/Reselection defined in the 3GPP specification “TS25.304”. As illustrated in the figure, when the mobile terminal is powered with the USIM uninserted, the mobile terminal becomes the status “Any Cell Selection” (see (1) of FIG. 19). If a mobile communication base station that is communicable from the perspective of radio wave strength is found, the mobile terminal shifts from the status “Any Cell Selection” to the status “Camped on any cell” (see (2) of FIG. 19).
If the USIM is inserted into the mobile terminal (see (3) of FIG. 19) and a mobile communication base station that is communicable with the mobile terminal from the perspective of radio wave strength is found, the mobile terminal shifts from the status “Any Cell Selection” to the status “Camped Normally” (see (4) of FIG. 19). However, if the mobile terminal cannot maintain the status normally communicable with the mobile communication base station, the mobile terminal shifts from the status “Camped Normally” back to the status “Any Cell Selection” (see (5) of FIG. 19). Even when the USIM is inserted, if the Attach fails or if the location registration fails, the mobile terminal remains as the status “Any Cell Selection” (see (6) of FIG. 19); however, if the mobile terminal is communicable with a mobile communication base station of a HOME operator, an operator under a roaming contract with the HOME operator, or other operators from the perspective of radio wave strength, the mobile terminal shifts from the status “Any Cell Selection” to the status “Camped on any cell” in the same manner as in the case where a USIM is not inserted (see (7) of FIG. 19).
It means that when the mobile terminal is in the status “Camped Normally”, which is the normally communicable status defined in the 3GPP specification “TS25.304”, the mobile terminal is notified of the emergency call code information by the MSC.
However, in the above-described technology, there is a problem in that a mobile terminal with the status “Camped on any cell” cannot acquire the emergency call code information.